VSAN-Troubleshooting-Reference-Manual

Diagnostics and Troubleshooting Reference Manual – Virtual SAN
Predictive reporting - smartd
In ESXi 5.1, VMware introduced support for SMART, Self-Monitoring, Analysis and
Reporting Technology for disk drives. If a drive supports SMART, some useful fields
can be extracted from the disk drive, especially solid-state disks, which can help
with proactive reporting. For example, it can help determine if there are any read or
write errors counting, or the drive overheating, and so on.
Unfortunately, not every drive supports every smart parameter, and the output may
contain some fields displayed as N/A as shown below. Some drives that do not
support smart will show every field as N/A. However, for drives that do support
smart, some really useful information can be extracted using the command shown
here:
esxcli storage core device smart get
[root@cs-tse-d01:~] esxcli storage core device smart get -d
t10.ATA_____DELL_P320h2DMTFDGAL175SAH_____
___________0000000012270202CF28
Parameter
Value Threshold Worst
---------------------------- ----- --------- -----
Health Status OK N/A N/A
Media Wearout Indicator N/A N/A N/A
Write Error Count 0 0 0
Read Error Count 0 0 100
Power-on Hours 5890 0 100
Power Cycle Count 21 0 100
Reallocated Sector Count N/A N/A N/A
Raw Read Error Rate N/A N/A N/A
Drive Temperature 37 87 47
Driver Rated Max Temperature 102 N/A N/A
Write Sectors TOT Count N/A N/A N/A
Read Sectors TOT Count N/A N/A N/A
Initial Bad Block Count 1 0 100
[root@cs-tse-d01:~]
Note that when RAID 0 is used on the controller to present disk devices to the ESXi
host, on many occasions the controller blocks the SMART (Self-Monitoring, Analysis
and Reporting Technology) information and disk type information. This is another
reason to use controllers that support pass-through mode where possible.
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